code: def _infer_type(node):
      """A method to infer the type of a relay expression."""
      mod = tvm.IRModule.from_expr(node)
      mod = transform.InferType()(mod)
      entry = mod["main"]
      return entry if isinstance(node, relay.Function) else entry.body
  
file_path: tvm/python/tvm/autotvm/graph_tuner/utils/traverse_graph.py
imports: import threading
  import re
  import tvm
  from tvm import relay, autotvm
  from tvm.relay import transform
  from tvm.relay.expr import Call, TupleGetItem, Var, Constant, Tuple
  from tvm.relay.function import Function
  from tvm.relay.ty import TupleType, TensorType
  from tvm.autotvm.task import TaskExtractEnv
  from .utils import has_multiple_inputs, is_boundary_node, is_skipped_node
  from .._base import OPT_OUT_OP
label_desc: Use image node_id 2 for calling a global function with example usage: _infer_type(node) and returns: unknown